work uses pypi every day, and I had to set up a caching proxy because mirrors are frequently unavailable. It was inconceivable coming from CPAN that the major package distribution network for a major language may be down.
OT but I think it's one of the reasons mandrake/mandriva never quite took off. There was never a great centralized repository network you could count no - I grew tired of using the PLF system to grab a list of mirrors, and having to update it all the time because participating mirrors were offline or defunct after a few weeks/months.
I had to deal with the major third party, more or less essential, Ruby and RoR gems a few years ago. Rubyforge was a part of this constellation of essential third party gems. Dealing with gems was definitely dependency hell, with mixed up cross dependencies, which were dependent on certain versions of other gems, that were sometimes conflicting when there were a number of gems. Also, you would go to the main Ruby web pages and click links to documentation and the links would be broken - not some obscure, old documentation page to another old, obscure module, but from central help web pages to other pages of central importance.
I have used CPAN for many years and it is so much more rock solid and automagic. If a mirror is down it jumps to the next one without a beat.
The CPAN modules are great too. I was using XML:Simple recently, but the XML files got too big. So I looked around a little and started using XML:Twig, which works great. Then I needed to sort alphabetically words in a variety of languages. So I went with Sort:ArbBiLex which allows me to create my own sort dictionary and has suggested Western language dictionaries on the documentation page. And yes, it has a cmp call which allows for easy multi-column sorting. For whatever problem I have, it seems someone has already written a module for it, which I can get going with little effort.